Checksum mismatch for the distfile of tbb 4.0.0: http://threadingbuildingblocks.org/uploads/78/174/4.0/tbb40_233oss_src.tgz
It appears that the MASTER_SITE has been re-organized and redirects to a download page.
How-To-Repeat: 1. cd /usr/ports/tbb
Over to maintainer (via the GNATS Auto Assign Tool)
Port fixed, thanks!